id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
1593589979,I_kwDOAMm_X85e_EDb,7545,DataArrray.resample() appears to ignore skipna parameter while taking annual mean,76110149,open,0,,,3,2023-02-21T14:33:46Z,2023-02-21T17:04:46Z,,CONTRIBUTOR,,,,"### What happened?

The skipna parameter appears to have no effect while annually resampling a monthly DataArray.
I'm not sure if this is related to [#6772](https://github.com/pydata/xarray/issues/6772)


### What did you expect to happen?

I expected `da_yrA` to be NaN since I am not skipping NaN values.

### Minimal Complete Verifiable Example

```Python
import numpy as np
import pandas as pd
import xarray as xr

data = np.arange(12)
month_index = pd.date_range(""2022-01"",""2022-12-31"", freq=""M"")
df = pd.DataFrame(index=month_index, data=data)
df.index.name = ""time""
df.columns.name = ""value""
df.loc[""2022-01"":""2022-02""] = np.nan
da = xr.DataArray(df)

# these unexpectedly produce the same result
da_yrA = (da).resample(time=""A-Dec"", skipna=False).mean()
da_yrB = (da).resample(time=""A-Dec"", skipna=True).mean()

print(da_yrA)
print(da_yrB)
```


### MVCE confirmation

- [X] Minimal example — the example is as focused as reasonably possible to demonstrate the underlying issue in xarray.
- [X] Complete example — the example is self-contained, including all data and the text of any traceback.
- [X] Verifiable example — the example copy & pastes into an IPython prompt or [Binder notebook](https://mybinder.org/v2/gh/pydata/xarray/main?urlpath=lab/tree/doc/examples/blank_template.ipynb), returning the result.
- [X] New issue — a search of GitHub Issues suggests this is not a duplicate.

### Relevant log output

_No response_

### Anything else we need to know?

_No response_

### Environment

<details>

```
scipy: 1.10.0
netCDF4: 1.6.2
pydap: None
h5netcdf: None
h5py: None
Nio: None
zarr: None
cftime: 1.6.2
nc_time_axis: 1.4.1
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: None
dask: 2023.2.0
distributed: 2023.2.0
matplotlib: 3.7.0
cartopy: 0.21.1
seaborn: None
numbagg: None
fsspec: 2023.1.0
cupy: None
pint: None
sparse: 0.13.0
flox: None
numpy_groupies: None
setuptools: 67.3.2
pip: 23.0.1
conda: None
pytest: None
mypy: None
IPython: 8.10.0
sphinx: None
```

</details>
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/7545/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue